hello. i was just wondering if anyone could help me out with my 94 z28. i just bought it a month ago. it runs very good when you first start it but after it warms up it seems to miss. if i try to stomp it sometimes it will go fine but other times it will run like its missing a couple of cylinders. the dealer said it had newer opti. has newer waterpump. has msd wires. i replaced coil but that didnt help. service engine light comes on every once in a while but very seldom. has 160000 on the dash. car is very clean. like i said when its cold it doesnt miss at all. any info will be appreciated. Thanks. and also the car is completely stock besides an holley throttle body.

 

well my car was doing the same thing and i just replaced the optispark and no problems anymore

 

have it scanned for trouble codes. could save some bucks and time. only certain scanners will work on most 94s, they have obd 1 plug and a obd2 computer. i have heard of one so far that has the obd1 system only. may be worth calling around to see if the local parts stores are able to scan it.

 

yeah if the check engine light has come on then its set a code of some sort. get it scanned

 

if it was the opti? wouldnt it run like crap all the time, or just when its warmed up? and also does the check engine light have to be on to get a scan? it doesnt stay on, it will just come off and on very seldomly?

 

opti could do that but so could bad fuel pump,, maf, egr, or the ecu, also could be intermitant short or lose wire. probly missed a few. computer will set a code if a problem happens a few times. a good scanner will tell everything thats stored and sometimes there is some useful info besides the problem code.

 

where should i take it to get scanned? all the auto parts stores have the obd 2 scanner. they tell me to do the paper clip trick, but like i said 90% of the time the check engine light is off. will any automotive shop be able to scan it?

 

paper clip thing wont work on most 94s. u need a scanner that works on the obd1 computer with a obd2 plug. not alot of parts stores have the scanner for em or for that matter know what they are. call a couple shops and see if they can scann it for u and if they charge for it.

 

http://www.amazon.com/Actron-CP9145-...8084549&sr=8-1

http://cgi.ebay.com/ebaymotors/Actro...item19ba6ad3af


scans the 94 and 95 Z's as well as OBD2 so you'll have it around for a while

it's what I have

if you're a kid, ask mom and dad for an early present. You can use this on their check engine lights too!!!

 

thanks for all the help. had it scanned and turns out it was the drivers side upstream 02 sensor. i replaced it and now it doesnt miss a beat.